我正在使用这个code但我想让每个问题有 4 个选项。我还把问题减少到了 5 个。有人可以帮忙吗？这是修改后的代码。但它没有运行:(
QuizActivity.java
public class QuestionActivity extends Activity {
List<Question> quesList;
int score = 0;
int qid = 0;
Question currentQ;
TextView txtQuestion, times, scored;
Button button1, button2, button3, button4;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
QuizHelper db = new QuizHelper(this);
quesList = db.getAllQuestions();
currentQ = quesList.get(qid);
txtQuestion = (TextView) findViewById(R.id.txtQuestion);
button1 = (Button) findViewById(R.id.button1);
button2 = (Button) findViewById(R.id.button2);
button3 = (Button) findViewById(R.id.button3);
button4 = (Button) findViewById(R.id.button4);
scored = (TextView) findViewById(R.id.score);
times = (TextView) findViewById(R.id.timers);
setQuestionView();
times.setText("00:02:00");
CounterClass timer = new CounterClass(60000, 1000);
timer.start();
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getAnswer(button1.getText().toString());
}
});
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getAnswer(button2.getText().toString());
}
});
button3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getAnswer(button3.getText().toString());
}
});
button4.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getAnswer(button4.getText().toString());
}
});
}
public void getAnswer(String AnswerString) {
if (currentQ.getANSWER().equals(AnswerString)) {
score++;
scored.setText("Score : " + score);
} else {
Intent intent = new Intent(QuestionActivity.this,
ResultActivity.class);
Bundle b = new Bundle();
b.putInt("score", score); // Your score
intent.putExtras(b); // Put your score to your next
startActivity(intent);
finish();
}
if (qid < 4) {
currentQ = quesList.get(qid);
setQuestionView();
} else {
Intent intent = new Intent(QuestionActivity.this,
ResultActivity.class);
Bundle b = new Bundle();
b.putInt("score", score); // Your score
intent.putExtras(b); // Put your score to your next
startActivity(intent);
finish();
}
}
@TargetApi(Build.VERSION_CODES.GINGERBREAD)
@SuppressLint("NewApi")
public class CounterClass extends CountDownTimer {
public CounterClass(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
@Override
public void onFinish() {
times.setText("Time is up");
}
@Override
public void onTick(long millisUntilFinished) {
long millis = millisUntilFinished;
String hms = String.format(
"%02d:%02d:%02d",
TimeUnit.MILLISECONDS.toHours(millis),
TimeUnit.MILLISECONDS.toMinutes(millis)
- TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS
.toHours(millis)),
TimeUnit.MILLISECONDS.toSeconds(millis)
- TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS
.toMinutes(millis)));
System.out.println(hms);
times.setText(hms);
}
}
private void setQuestionView() {
txtQuestion.setText(currentQ.getQUESTION());
button1.setText(currentQ.getOPTA());
button2.setText(currentQ.getOPTB());
button3.setText(currentQ.getOPTC());
button4.setText(currentQ.getOPTD());
qid++;
}
}
QuizHelper.java
public class QuizHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "mathsone";
private static final String TABLE_QUEST = "quest";
private static final String KEY_ID = "qid";
private static final String KEY_QUES = "question";
private static final String KEY_ANSWER = "answer"; // correct option
private static final String KEY_OPTA = "opta"; // option a
private static final String KEY_OPTB = "optb"; // option b
private static final String KEY_OPTC = "optc"; // option c
private static final String KEY_OPTD = "optd"; // option d
private SQLiteDatabase dbase;
public QuizHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
dbase = db;
String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_QUEST + " ( "
+ KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_QUES
+ " TEXT, " + KEY_ANSWER + " TEXT, " + KEY_OPTA + " TEXT, "
+ KEY_OPTB + " TEXT, " + KEY_OPTC + " TEXT " + KEY_OPTD + " TEXT)";
db.execSQL(sql);
addQuestion();
// db.close();
}
private void addQuestion() {
Question q1 = new Question("5+2 = ?", "7", "8", "6", "5", "7");
this.addQuestion(q1);
Question q2 = new Question("2+18 = ?", "18", "19", "20", "17", "20");
this.addQuestion(q2);
Question q3 = new Question("10-3 = ?", "6", "7", "8", "5", "7");
this.addQuestion(q3);
Question q4 = new Question("5+7 = ?", "12", "13", "14", "11", "12");
this.addQuestion(q4);
Question q5 = new Question("3-1 = ?", "1", "3", "2", "4", "2");
this.addQuestion(q5);
// END
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldV, int newV) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUEST);
onCreate(db);
}
// Adding new question
public void addQuestion(Question quest) {
// SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_QUES, quest.getQUESTION());
values.put(KEY_ANSWER, quest.getANSWER());
values.put(KEY_OPTA, quest.getOPTA());
values.put(KEY_OPTB, quest.getOPTB());
values.put(KEY_OPTC, quest.getOPTC());
values.put(KEY_OPTD, quest.getOPTD());
// Inserting Row
dbase.insert(TABLE_QUEST, null, values);
}
public List<Question> getAllQuestions() {
List<Question> quesList = new ArrayList<Question>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_QUEST;
dbase = this.getReadableDatabase();
Cursor cursor = dbase.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Question quest = new Question();
quest.setID(cursor.getInt(0));
quest.setQUESTION(cursor.getString(1));
quest.setANSWER(cursor.getString(2));
quest.setOPTA(cursor.getString(3));
quest.setOPTB(cursor.getString(4));
quest.setOPTC(cursor.getString(5));
quest.setOPTD(cursor.getString(6));
quesList.add(quest);
} while (cursor.moveToNext());
}
return quesList;
}
}
问题.java
public class Question extends Activity {
private int ID;
private String QUESTION;
private String OPTA;
private String OPTB;
private String OPTC;
private String OPTD;
private String ANSWER;
public Question() {
ID = 0;
QUESTION = "";
OPTA = "";
OPTB = "";
OPTC = "";
OPTD = "";
ANSWER = "";
}
public Question(String qUESTION, String oPTA, String oPTB, String oPTC,String oPTD,
String aNSWER) {
QUESTION = qUESTION;
OPTA = oPTA;
OPTB = oPTB;
OPTC = oPTC;
OPTD = oPTD;
ANSWER = aNSWER;
}
public int getID() {
return ID;
}
public String getQUESTION() {
return QUESTION;
}
public String getOPTA() {
return OPTA;
}
public String getOPTB() {
return OPTB;
}
public String getOPTC() {
return OPTC;
}
public String getOPTD() {
return OPTD;
}
public String getANSWER() {
return ANSWER;
}
public void setID(int id) {
ID = id;
}
public void setQUESTION(String qUESTION) {
QUESTION = qUESTION;
}
public void setOPTA(String oPTA) {
OPTA = oPTA;
}
public void setOPTB(String oPTB) {
OPTB = oPTB;
}
public void setOPTC(String oPTC) {
OPTC = oPTC;
}
public void setOPTD(String oPTD) {
OPTD = oPTD;
}
public void setANSWER(String aNSWER) {
ANSWER = aNSWER;
}
}
然后对于activity_main.xml，我添加了一个id为button4的android按钮。
<Button
android:id="@+id/button4"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="80dp"
android:layout_marginRight="80dp"
android:layout_marginTop="5dp"
android:background="#fff"
android:gravity="center"
android:text="31"
android:textColor="#000000"
android:textSize="25.0sp" />
这是我的日志:
FATAL EXCEPTION: main
Process: versionone.example, PID: 2252
java.lang.RuntimeException: Unable to start activity ComponentInfo{versionone.example/versionone.example.QuestionActivity}: java.lang.IllegalStateException: Couldn't read row 0, col 6 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.IllegalStateException: Couldn't read row 0, col 6 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it.
at android.database.CursorWindow.nativeGetString(Native Method)
at android.database.CursorWindow.getString(CursorWindow.java:434)
at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51)
at versionone.example.QuizHelper.getAllQuestions(QuizHelper.java:90)
at versionone.example.QuestionActivity.onCreate(QuestionActivity.java:38)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
最佳答案
+ KEY_OPTB + " TEXT, " + KEY_OPTC + " TEXT, " + KEY_OPTD + " TEXT)";
您在表创建 SQL 中的 KEY_OPTC 后面漏掉了一个逗号。
关于java - 如何向预制的 Android 程序添加另一个按钮 (Android Studio)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/35484812/